Hair clipper



June 1 1926. 1586,92 1

- A. L. UNDELAND ET AL HAIR CLIPPER Filed May 31 1923 31M. awliozo: A UNDELAND. 17. C. K121 Y.

Patented June 1, 1926.

I STATES ti re PATENT. cries.

ANDREW L. UNDELAND AND HOBART G. KELLY, OF OMAI-IA, NEBRASKA; SAID KELLY ASSIGNOR 'IO SAID UNDELA'ND.

HAIR CLIPPER.

Application filed May 31, 1923. Serial No. 642,559.

' Our invention relates to hair clippers and particularly tothe blades or cutters thereof. It is the object of our invention to provide an improved form of blades for hair clippers, whereby to furnish a perfectly fitted guide between the blades for holding them in operative alinement with each other, to provide a Variable stop for limiting the relative longitudinal movement of the blades andto provide blades which may be readily sharpened by a simple surface-grinding operation, and with the removal of a minimum amount of material from the blades.

In the accompanying drawings Fig. 1 is a side view of a hair clipper provided with blades embodying our invention, Fig. 2 is a plan View of the same with the clampcover and upper blade removed, Fig. 3 is a bottom view of the upper blade, Fig. l is a transverse section of the same on the line H of Fig. 3, and Fig. 5 is a detail transversesection of the lower or main blade onthe line 5-5 of Fig. 2.

The clipper shown in the drawings has r handles of the ordinary form, substantially standardized for hand-operatedhair clippers, the main handle 6 having a terminal head 7 with a flat lower face to which the lower blade or cutter is detachably secured by means of screws 8 which extend through the blade from the lower side and enter threaded openings in the head. Adjacent to the head 7 is the spring-barrel 9, and in front of the spring-barrel there is a post or stud 10 which extends up vertically from the head. The second or movable handle 11 is pivoted on said post 10, and has an arm 12 which extends forwardly and downwardly to terminate above the central portion of the lower blade. The upper portion of the post 10 is threaded to re ceive a wing-nut 13 which is employed to hold the clamp or cover 14, said member forming a housing over the blade-actuating arm 12, and serving also to press the upper clipper-blade against the lower, whereby tomaintain the shearing relation of the blades.

The lower clipper-blade comprises a bodyportion 16.0f which the upper surface of the rear portion fits against the lower face of the head 7, to which the blade is secured by the screws 8. The front edge of the blade is notched to form the usual V-shaped teeth 17, and the lower side of the blade is beveledso that the toothed front edge is thinner than the main body. The upper blade 18 has teeth 19 adapted to register with the teeth 17 of the lower or main blade, and the upper side ofsaid blade 18 is beveled at both the front and rear edges. The rear edge of the blade 18 has a wide V-shaped notch therein, leadingto a oentral reotangularnotch 20 which is adapted Vention, the contacting faces of the pair of blades are limited to narrow longitudinal strips adjoining the front and rear edges of the upper blade, and at corresponding portlons of the lower blade, said front and rear contact-faces of the upper blade being designated,respectively, as 21 and 22, and the corresponding faces of the lower blade being designated as 23 and 24. Each pair of the contact-faces is in a common plane, so that the blades may be sharpened by a simple surfacegrinding operation, in volving the removal of only a very small quantity of metal from the blades in order to present fresh cutting-edges at the sides of the teeth. The face 25 at the rear upper portion of the main blade 16, which engages the lower side of the head 7, is offset or depressed below the level of theadjacent contact-face 24:, the amount of the offset being as much as the. greatest depth to which the contact-faces may be ground be fore the blade is worn out. Similarly, between the faces 21 and 22 of the upper blade, and between the faces 23 and 24 of the lower blade, the respective surfaces 26' and 27 are offset from the plane of the contactfaces, so as not to be touched during the grinding of the contact-faces for sharpening the blades.

At the front edge of the contact strip or face 22 of the upper blade there is a rela tively deep longitudinal rectangular groove 28, and in the lower blade there is a similar groove 29 adjoining the front edge of the strip or face 24. Said grooves 28 and 29 are adapted to receive slidably the guideblocks 30, which are disposed between the blades as indicated in Fig. 1, the lower portion of each block resting in the groove 29 and the upper portion of each block extending into the groove 28. The depth or,

thickness of the blocks is preferably made less than the combined depth of the grooves 28 and 29 when the blades are new, so that when the depth of said grooves is reduced by grinding of the contact-faces it will not be necessary to reduce the thickness of the guide-blocks in order to allowthe contactfaces to engage each other. At the inner ends thereof each of the guide-blocks has a beveled corner 33, as shown in Fig. 2, for a purpose which will presently appear.

As the grooves 28 and 29 extendfrom end to end of the blades, it is necessary that means be provided for preventing the guideblocks moving endwise out of the grooves, and the preferred means for so limiting the longitudinal movement of the guide-blocks consists of lugs 31 extending into the groove 29 from the front side near the ends thereof. Said lugs 31 are integral with the body of the blade, portions of the metal being swaged out from the material at the front of the groove by sharply striking the surface 26 with a punch having a flat rectangular end of which a portion extends over the groove. The punch forms a small depression 32 in the surface 26, and the material displaced from said depression constitutes the stop-lug. The swaging operation to form the stop-lugs is done, of course, before the blade is heat-treated to harden and temper the same.

In hand-operated hair-clippers it is desirable that the permissible stroke or travel of the upper blade, relative to the lower blade, be a multiple of the pitch of the teeth 17 and 19, so that at each limit of movement the pairs of teeth will be in register with each other. This result is attained in our structure by so proportioning the length of the guide-blocks that when the outer ends engage thestop-lugs 31 the distance between the adjacent ends of the blocks will be the required travel of the actuating-arm 12, of which the terminal portion extends through the notch 20 of the upper blade into the space between said adjacent ends of the guide-blocks.

For power-driven hair-clippers the stroke of, the blade is fixed and determined by the driving means for the actuating-arm, and it is undesirable to have fixed stops for limiting the travel of said arm or of the blade,

since the slightest mis-adjustment or wear of the actuating means would then result in pounding or hammering ofthe parts against one or both of the steps. To enable the use of our blades on power-driven clippers, it

is merely necessary to slightly increase the permissible stroke of the blade, making the same greater than the actual stroke imparted by the actuating means, and this is effected by reversing or turning the guideblocks 30 end for end, so that the beveled corners 33 are adjacent to the stop-lugs 31. It will be seen that when the blocks are so positioned they may move closer to the ends of the groove 29, thus increasing the distance between the adjacent or inner ends thereof, which is the distance determining the maximum stroke of the actuating-arm. All electric power or motor-driven hair-clippers in common use are so designed as to employ blades of the same form as those used in hand-actuated clippers, with the sole exception that the stroke of the blade is not determined by fixed stops, and it will thus be apparent that our blades may be used interchangeably with the blades commonly provided for both classes of clippers.

It will be seen that the long bearing and guiding surfaces, provided by the blocks 30 and grooves 28 and 29, will result in our blades being maintained in perfect operative alinement with each other when in use, and that when the blades are removed for grinding, the contactsurfaces 21, 22, 23 and 2a are immediately accessible without removal of posts, pins or other devices usually provided for interconnecting the pair of blades. 7

Now, having described our invention, what we claim and desire to secure by Letters Patent is:

1. In a hair-clipper, a pair of blades provided in their adjacent faces with registering longitudinal grooves, guide-blocks of a thickness less than the combined depth of said grooves, said guide-blocks fitting slidably in said grooves, and means for limiting movement of said guide-blocks longitudinally.

2. In a hair-clipper, a pair of blades having grindable longitudinally extending contact-faces spaced apart transversely and raised above all other face-portions thereof, registering longitudinal grooves intermediate said raised contact-faoes, guide-blocks fitting slidably in said registering grooves, and stops formed integrally with one blade and extending into the longitudinal groove thereof to limit movement of the guideblocks therein. I I

8. In a hair-clipper, a pair of blades pro vided in their adjacent faces with registering longitudinal grooves, guide-blocks fitting slidably in said registering grooves, and stops on one of said blades for limiting longitudinal movement of the guide-blocks relative thereto.

4. In a hair-clipper, a main blade havin a face adapted to engage a clipper-hea means for detachably securing said blade to said head, said blade having longitudinal transversely spaced contact-faces raised above said head-engaging face and having a longitudinal groove intermediate said raised contact-faces, a second blade having raised contact-faces adapted for engagement with the contact-faces of the main blade and having an intermediate groove adapted to register With the groove of said main blade, guide-blocks fitting slidably Within the registering grooves of both blades, said second blade being notohed to receive an actuatingarm so that a portion of said arm may ex,- tend into the groove between adjacent ends of the guide-blocks, and means on the main blade for limiting longitudinal movement of the guide-blocks.

ANDREW L. UNDELAND. HOBART o; KELLY. 

